Construction of nested space-filling designs

New types of designs called nested space-filling designs have been proposed for conducting multiple computer experiments with different levels of accuracy. In this article, we develop several approaches to constructing such designs. The development of these methods also leads to the introduction of several new discrete mathematics concepts, including nested orthogonal arrays and nested difference matrices.Comment: Published in at http://dx.doi.org/10.1214/09-AOS690 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

A reinforced learning approach to optimal design under model uncertainty

Optimal designs are usually model-dependent and likely to be sub-optimal if the postulated model is not correctly specified. In practice, it is common that a researcher has a list of candidate models at hand and a design has to be found that is efficient for selecting the true model among the competing candidates and is also efficient (optimal, if possible) for estimating the parameters of the true model. In this article, we use a reinforced learning approach to address this problem. We develop a sequential algorithm, which generates a sequence of designs which have asymptotically, as the number of stages increases, the same efficiency for estimating the parameters in the true model as an optimal design if the true model would have correctly been specified in advance. A lower bound is established to quantify the relative efficiency between such a design and an optimal design for the true model in finite stages. Moreover, the resulting designs are also efficient for discriminating between the true model and other rival models from the candidate list. Some connections with other state-of-the-art algorithms for model discrimination and parameter estimation are discussed and the methodology is illustrated by a small simulation study

Interaction balance in symmetrical factorial designs with generalized minimum aberration

Abstract: In this paper, the issue of balance pattern of the interaction columns of a symmetrical design is considered according to orthogonal components system. The minimum interaction unbalance criterion is proposed for ranking and comparing s-level factorial designs, where s is any a prime or a prime power. It is further showed that the interaction unbalance pattern is just the generalized wordlength pattern defined b

Expert Consensus on Microtransplant for Acute Myeloid Leukemia in Elderly Patients -Report From the International Microtransplant Interest Group

Recent studies have shown that microtransplant (MST) could improve outcome of patients with elderly acute myeloid leukemia (EAML). To further standardize the MST therapy and improve outcomes in EAML patients, based on analysis of the literature on MST, especially MST with EAML from January 1st, 2011 to November 30th, 2022, the International Microtransplant Interest Group provides recommendations and considerations for MST in the treatment of EAML. Four major issues related to MST for treating EAML were addressed: therapeutic principle of MST (1), candidates for MST (2), induction chemotherapy regimens (3), and post-remission therapy based on MST (4). Others included donor screening, infusion of donor cells, laboratory examinations, and complications of treatment

An Automatic Tree Skeleton Extraction Approach Based on Multi-View Slicing Using Terrestrial LiDAR Scans Data

Effective 3D tree reconstruction based on point clouds from terrestrial Light Detection and Ranging (LiDAR) scans (TLS) has been widely recognized as a critical technology in forestry and ecology modeling. The major advantages of using TLS lie in its rapidly and automatically capturing tree information at millimeter level, providing massive high-density data. In addition, TLS 3D tree reconstruction allows for occlusions and complex structures from the derived point cloud of trees to be obtained. In this paper, an automatic tree skeleton extraction approach based on multi-view slicing is proposed to improve the TLS 3D tree reconstruction, which borrowed the idea from the medical imaging technology of X-ray computed tomography. Firstly, we extracted the precise trunk center and then cut the point cloud of the tree into slices. Next, the skeleton from each slice was generated using the kernel mean shift and principal component analysis algorithms. Accordingly, these isolated skeletons were smoothed and morphologically synthetized. Finally, the validation in point clouds of two trees acquired from multi-view TLS further demonstrated the potential of the proposed framework in efficiently dealing with TLS point cloud data

Multistratum fractional factorial split-plot designs with minimum aberration and maximum estimation capacity

This paper introduces minimum secondary aberration (MSA) and maximum secondary estimation capacity (MSEC) criteria for discriminating among rival nonisomorphic regular multistratum fractional factorial split-plot (FFSP) designs. Some general rules for identifying MSA or MSEC multistratum FFSP designs through their consulting designs are also established. It is an improvement and generalization of the related results in (Statist. Sinica 12 (2002) 885). The comparison between the MSEC criterion and that of Mukerjee and Fang (2002) is briefly given.Consulting design Estimation capacity Minimum secondary aberration Multistratum Fractional factorial split-plot design Projective geometry